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From: Don Y <blockedofcourse@foo.invalid>
Newsgroups: sci.electronics.design
Subject: Re: CAT5e cable
Date: Sun, 20 Apr 2025 15:56:08 -0700
Organization: A noiseless patient Spider
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On 4/20/2025 2:15 PM, Joe Gwinn wrote:
>> My concern is mainly to know how to specify the type of cable
>> that should be used in future installations (in which I won't
>> likely be involved).  Other than naming a specific vendor
>> and model number (whose manufacture could also change, over
>> time)

>> As I suspect "paid help" would be less meticulous than I, it
>> would be wise to specify materials that they would be less
>> likely to abuse.  <frown>
> 
> The simplest way I know of is to get samples and cut them open for
> detail inspection.

That only works for the samples you have in your hands.
I don't see any criteria that is *specified* for the
cables that highlights the differences that I am seeing.

If I specify "Belden xyz" or "Southwire abc", there's no
guarantee that they won't change how they are manufactured.
Or, the aspect that I'm concerned with.

Or, simply stop making it.

So, I'm looking for a way of specifying the criteria that
are important -- and, ideally, of extracting it from a
manufacturer's datasheet.

> Without destructive inspection, there are a few tests.   First, mass
> per length - heavier is better.

Weight is likely something that can be easily determined -- even
without actual samples in your hands.  And, holding the wire gauge
constant, you'd have to assume any weight differences were due to
changes in insulation and/or jacket.

Unless, of course, they also include the weight of the packaging...

>  Second is DC resistance of each
> conductor per length - smaller is better.  For shielded twisted pair,
> the shield quality can be measured, but this requires special tools.
> 
> Joe Gwinn